Export FreeCAD Assembly to STEP AP214

Exporting assemblies from FreeCAD to the STEP AP214 format allows you to retain component hierarchy, sub-assemblies, and object colors when sharing CAD data with other engineering platforms. This guide explains how to properly configure FreeCAD's import/export preferences for AP214 and export your model tree to ensure the product structure remains fully intact.

1. Organize Your Model Hierarchy

To export a functioning assembly structure rather than a collection of disconnected solids, your components must be grouped within Part containers (App::Part).

  • Group individual bodies or components inside dedicated Part containers.
  • Nest sub-assemblies inside parent Part containers to define multi-level assembly hierarchies.
  • If you are using dedicated assembly workbenches (such as the Assembly Workbench in FreeCAD 1.0+, Assembly3, or Assembly4), ensure your root assembly node contains all parts and constraints properly resolved before exporting.

2. Configure Preferences for STEP AP214

FreeCAD must be set to write the STEP file using the AP214 schema instead of AP203, which does not support full structural assembly metadata or custom component colors:

  1. Go to the top menu and select Edit > Preferences.
  2. In the left-hand navigation pane, select Import-Export.
  3. Click on the STEP tab.
  4. Locate the Schema or STEP format dropdown menu.
  5. Select AP214IS (International Standard) or AP214CD.
  6. Check that Export single parts as compounds is disabled if you want nested structures to be recognized as native assembly components in target CAD applications.
  7. Click Apply and then OK to save the settings.

3. Select and Export the Root Assembly

  1. In the Tree View, click to select only the top-level parent Part or the root assembly container. Selecting individual bodies alongside the parent can cause duplicate geometry in the final export.
  2. Go to File > Export.
  3. In the export dialog, set the file type dropdown to STEP with colors (.step .stp).
  4. Specify your file name and target directory, then click Save.

The resulting STEP file will contain the complete assembly structure along with component names and color definitions, fully compatible with any CAD system supporting the STEP AP214 standard.